Patent US3868430A successfully refreshed from Google Patents.
US3868430A
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Process for the separation of ethylbenzene from xylenes
Assignee: Aquila SpA
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Filing: 1974-01-02
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Granted: 1975-02-25
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Expires: 1994-01-02
Abstract
Abstract In the known process comprising hydrogenation of a mixture of ethylbenzene and xylenes, separation of the ethylcyclohexane from other hydrogenated material, and dehydrogenation of ethylcyclohexane back to ethylbenzene, the improvement consists of a partial selective hydrogenation to a conversion of ethylbenzene of between 50 and 99%, preferably between 65 and 85% and a conversion of xylenes to between 10 and 50%.
Inventors
- 👤 Michele Giangaspero
- 👤 Giorgio Tlustos
- 👤 Marino Bose
- 👤 Domenico Corsi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 03:35
CPC Classifications
C; C07; C07C; C07C15/00; C07C15/02; C07C15/067; C07C15/073; C07C5/00; C07C5/02; C07C5/10; C07C7/00; C07C7/148; C07C7/163; C07C2601/00; C07C2601/12; C07C2601/14
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
145 words
IN A PROCESS FOR SEPARATION OF ETHYLBENZENE FROM A MIXTURE COMPRISING ESSENTIALLY ETHYLBENZENE AND XYLENES COMPRISING THE SUCCESSIVE STEPS OF: SEPARATING THE MIXTURE INTO A FRACTION CONTAINING ESSENTIALLY THE ORTHO-XYLENE PRESENT IN THE MIXTURE, A FRACTION CONTAINING ESSENTIALLY THE PARA-XYLENE AND A FRACTION CONTAINING ETHYLBENZENE, CATALYTICALLY HYDROGENATING THE FRACTION CONTAINING ETHYLBENZENE TO FORM A MIXTURE CONTAINING ETHYLCYCLOHEXANE SEPARATING, BY DISTILLATION, THE ETHYLCYCLOHEXANE FROM THE HYDROGENATION MIXTURE, AND CATALYTICALLY DEHYDROGENATING THE ETHYLCYCLOHEXANE INTO ETHYLBENZENE, THE IMPROVEMENT WHICH COMPRISES THE STEPS OF CARRYING OUT THE CATALYTIC HYDROGENATION PARTIALLY AND SELECTIVELY UNTIL THE CONVERSION OF ETHYLBENZENE INTO ETHYLCYCLOHEXANE IS BETWEEN 50 AND 99% OF THE ETHYLBENZENE SUBJECTED TO HYDROGENATION, THE CONVERSION OF XYLENES BEING BETWEEN 10 AND 50% OF THE XYLENES SUBJECTED TO HYDROGENATION, SEPARATING THE NON-HYDROGENATED XYLENES FROM THE PARTIALLY HYDROGENATED MIXTURES AND SEPARATING THE ETHYLCYCLOHEXANE AND THE NON-HYDROGENATED ETHYLBENZENE FROM THE REMAINDER OF THE HYDROGENATED MIXTURE.
Claim 2
Dependent Claim
145 words
IN A PROCESS FOR SEPARATION OF ETHYLBENZENE FROM A MIXTURE COMPRISING ESSENTIALLY ETHYLBENZENE AND XYLENES COMPRISING THE SUCCESSIVE STEPS OF: SEPARATING THE MIXTURE INTO A FRACTION CONTAINING ESSENTIALLY THE ORTHO-XYLENE PRESENT IN THE MIXTURE, A FRACTION CONTAINING ESSENTIALLY THE PARA-XYLENE AND A FRACTION CONTAINING ETHYLBENZENE, CATALYTICALLY HYDROGENATING THE FRACTION CONTAINING ETHYLBENZENE TO FORM A MIXTURE CONTAINING ETHYLCYCLOHEXANE SEPARATING, BY DISTILLATION, THE ETHYLCYCLOHEXANE FROM THE HYDROGENATION MIXTURE, AND CATALYTICALLY DEHYDROGENATING THE ETHYLCYCLOHEXANE INTO ETHYLBENZENE, THE IMPROVEMENT WHICH COMPRISES THE STEPS OF CARRYING OUT THE CATALYTIC HYDROGENATION PARTIALLY AND SELECTIVELY UNTIL THE CONVERSION OF ETHYLBENZENE INTO ETHYLCYCLOHEXANE IS BETWEEN 50 AND 99% OF THE ETHYLBENZENE SUBJECTED TO HYDROGENATION, THE CONVERSION OF XYLENES BEING BETWEEN 10 AND 50% OF THE XYLENES SUBJECTED TO HYDROGENATION, SEPARATING THE NON-HYDROGENATED XYLENES FROM THE PARTIALLY HYDROGENATED MIXTURES AND SEPARATING THE ETHYLCYCLOHEXANE AND THE NON-HYDROGENATED ETHYLBENZENE FROM THE REMAINDER OF THE HYDROGENATED MIXTURE.
Claim 3
Dependent Claim
133 words
In a process for separation of ethylbenzene from a mixture comprising essentially ethylbenzene, para-xylene and meta-xylene comprising the successive steps of: separating a fraction containing essentially the para-xylene, catalytically hydrogenating the mixture remaining after separation of the para-xylene to form a mixture containing ethylcyclohexane, separating, by distillation, the ethylcyclohexane from the other constituents of the hydrogenation mixture, and catalytically dehydrogenating the ethylcyclohexane into ethylbenzene, the improvement which comprises carrying out the catAlytic hydrogenation partially and selectively until the conversion of ethylbenzene into ethylcyclohexane is between 50 and 99% of the ethylbenzene subjected to hydrogenation, the conversion of meta-xylene being between 10 and 50% of the meta-xylene subjected to hydrogenation, separating the non-hydrogenated xylenes from the partially hydrogenated mixture and separating the ethylcyclohexane and the non-hydrogenated ethylbenzene from the remainder of the hydrogenated mixture.
Claim 4
Dependent Claim
133 words
In a process for separation of ethylbenzene from a mixture comprising essentially ethylbenzene, para-xylene and meta-xylene comprising the successive steps of: separating a fraction containing essentially the para-xylene, catalytically hydrogenating the mixture remaining after separation of the para-xylene to form a mixture containing ethylcyclohexane, separating, by distillation, the ethylcyclohexane from the other constituents of the hydrogenation mixture, and catalytically dehydrogenating the ethylcyclohexane into ethylbenzene, the improvement which comprises carrying out the catAlytic hydrogenation partially and selectively until the conversion of ethylbenzene into ethylcyclohexane is between 50 and 99% of the ethylbenzene subjected to hydrogenation, the conversion of meta-xylene being between 10 and 50% of the meta-xylene subjected to hydrogenation, separating the non-hydrogenated xylenes from the partially hydrogenated mixture and separating the ethylcyclohexane and the non-hydrogenated ethylbenzene from the remainder of the hydrogenated mixture.
Claim 5
Dependent Claim
119 words
In a process for the separation of ethylbenzene from a mixture comprising essentially ethylbenzene and meta-xylene comprising the successive steps of: catalytically hydrogenating the mixture to form a mixture containing ethylcyclohexane, separating, by distillation, the ethylcyclohexane from the other constituents of the hydrogenated mixture, and catalytically dehydrogenating ethylcyclohexane to ethylbenzene, the improvement which comprises carrying out the catalytic hydrogenation partially and selectively until the conversion of ethylbenzene into ethylcyclohexane is between 50 and 99% of the ethylbenzene subjected to hydrogenation, the conversion of meta-xylene being between 10 and 50% of the meta-xylene subjected to hydrogenation; separating the non-hydrogenated meta-xylene from the partially hydrogenated mixture and separating the ethylcyclohexane and the non-hydrogenated ethylbenzene from the remainder of the hydrogenated mixture.
Claim 6
Dependent Claim
119 words
In a process for the separation of ethylbenzene from a mixture comprising essentially ethylbenzene and meta-xylene comprising the successive steps of: catalytically hydrogenating the mixture to form a mixture containing ethylcyclohexane, separating, by distillation, the ethylcyclohexane from the other constituents of the hydrogenated mixture, and catalytically dehydrogenating ethylcyclohexane to ethylbenzene, the improvement which comprises carrying out the catalytic hydrogenation partially and selectively until the conversion of ethylbenzene into ethylcyclohexane is between 50 and 99% of the ethylbenzene subjected to hydrogenation, the conversion of meta-xylene being between 10 and 50% of the meta-xylene subjected to hydrogenation; separating the non-hydrogenated meta-xylene from the partially hydrogenated mixture and separating the ethylcyclohexane and the non-hydrogenated ethylbenzene from the remainder of the hydrogenated mixture.
Claim 7
Dependent Claim
29 words
The improvement according to claim 1 wherein the selective catalytic hydrogenation is carried out in a single step until the conversion of the ethylbenzene is between 50 and 90%.
Claim 8
Dependent Claim
29 words
The improvement according to claim 2 wherein the selective catalytic hydrogenation is carried out in a single step until the conversion of the ethylbenzene is between 50 and 90%.
Claim 9
Dependent Claim
29 words
The improvement according to claim 3 wherein the selective catalytic hydrogenation is carried out in a single step until the conversion of the ethylbenzene is between 50 and 90%.
Claim 10
Dependent Claim
14 words
The improvement according to claim 4 wherein the conversion is between 65 and 85%.
Claim 11
Dependent Claim
14 words
The improvement according to claim 5 wherein the conversion is between 65 and 85%.
Claim 12
Dependent Claim
14 words
The improvement according to claim 6 wherein the conversion is between 65 and 85%.
Claim 13
Dependent Claim
55 words
The improvement according to claim 1 wherein the selective catalytic hydrogenation is carried out in two steps: the charge of the first step being composed of the initial mixture, the charge of the second step being composed of the non-hydrogenated xylenes and a little ethylbenzene separated by distillation from the first step of the hydrogenation.
Claim 14
Dependent Claim
55 words
The improvement according to claim 2 wherein the selective catalytic hydrogenation is carried out in two steps: the charge of the first step being composed of the initial mixture, the charge of the second step being composed of the non-hydrogenated xylenes and a little ethylbenzene separated by distillation from the first step of the hydrogenation.
Claim 15
Dependent Claim
41 words
The improvement according to claim 3 wherein the selective catalytic hydrogenation is carried out in two steps, the charge of the second hydrogenation step being composed of the non-hydrogenated meta-xylene and a little ethylbenzene from the first step of the hydrogenation.
Claim 16
Dependent Claim
71 words
The improvement according to claim 10 which further comprises distilling the hydrogenated material from the second step of the hydrogenation principally to separate the non-hydrogenated xylenes from the hydrogenated material, combining the remainder of the hydrogenated material from said distillation with the remainder of the hydrogenated material from the first step of the hydrogenation and distilling said combined materials to separate the ethylcyclohexane and the ethylbenzene which constitute the dehydrogenation charge.
Claim 17
Dependent Claim
71 words
The improvement according to claim 11 which further comprises distilling the hydrogenaTed material from the second step of the hydrogenation principally to separate the non-hydrogenated xylenes from the hydrogenated material, combining the remainder of the hydrogenated material from said distillation with the remainder of the hydrogenated material from the first step of the hydrogenation and distilling said combined materials to separate the ethylcyclohexane and the ethylbenzene which constitute the dehydrogenation charge.
Claim 18
Dependent Claim
71 words
The improvement according to claim 12 which further comprises distilling the hydrogenated material from the second step of the hydrogenation principally to separate the non-hydrogenated meta-xylene from the hydrogenated material combining the remainder of said hydrogenated material from said distillation with the remainder of the hydrogenated material from the first step of the hydrogenation and distilling said combined materials to separate the ethylcyclohexane and the ethylbenzene which constitute the dehydrogenation charge.
Claim 19
Dependent Claim
34 words
The improvement according to claim 15 which further comprises recycling a part of the fraction containing principally non-hydrogenated meta-xylene from the hydrogenated material of the second step back into the second step of hydrogenation.
Claim 20
Dependent Claim
35 words
The improvement according to claim 12 which further comprises recycling a part of the fraction containing non-hydrogenated meta-xylene and a little ethylbenzene from the first step of hydrogenation back to the first step of hydrogenation.
Claim 21
Dependent Claim
35 words
The improvement according to claim 16 which further comprises recycling a part of the fraction containing non-hydrogenated meta-xylene and a little ethylbenzene from the first step of hydrogenation back to the first step of hydrogenation.
Claim 22
Dependent Claim
31 words
The improvement according to claim 15 which further comprises recycling a part of the fraction containing non-hydrogenated meta-xylene from the second step of hydrogenation back into the first step of hydrogenation.
Claim 23
Dependent Claim
41 words
The improvement according to claim 10 wherein the conversion of ethylbenzene in the first step of the hydrogenation is between 50 and 90% and the total conversion of ethylbenzene after the second step of the hydrogenation is between 75 and 99%.
Claim 24
Dependent Claim
30 words
The improvement according to claim 20 wherein the conversion of ethylbenzene in the first step is between 65 and 85% and after the second step is between 88 and 98%.
Claim 25
Dependent Claim
40 words
The improvement according to claim 11 wherein the conversion of ethylbenzene in the first step of hydrogenation is between 50 and 90% and the total conversion of ethylbenzene after the second step of the hydrogenation is between 75 and 99%.
Claim 26
Dependent Claim
30 words
The improvement according to claim 22 wherein the conversion of ethylbenzene in the first step is between 65 and 85% and after the second step is between 88 and 98%.
Claim 27
Dependent Claim
41 words
The improvement according to claim 12 wherein the conversion of ethylbenzene in the first step of the hydrogenation is between 50 and 90% and the total conversion of ethylbenzene after the second step of the hydrogenation is between 75 and 99%.
Claim 28
Dependent Claim
30 words
The improvement according to claim 24 wherein the conversion of ethylbenzene in the first step is between 65 and 85% and after the second step is between 88 and 98%.
References Cited (Backward Citations)
US2282231A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-24 | 1978-08-26 | 1979-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-24 | 1982-08-26 | 1983-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-24 | 1986-08-26 | 1987-02-25 | $7700.00 | Window Closed / Lapsed |